#!/bin/bash

function diskspace() {
    clear
    df -k
}

function whoseon() {
    clear
    who
}

function memusage() {
    clear
    cat /proc/meminfo
}

PS3="Enter option: "
select option in "Display disk space"  \
    "Display logged on users" "Display memory usage" "Exit program"; do
    case $option in
    "Exit program")
        break ;;
    "Display disk space")
        diskspace ;;
    "Display logged on users")
        whoseon ;;
    "Display memory usage")
        memusage ;;
    *)
        clear
        echo "Sorry, wrong selection" ;;
    esac
done
clear

